With recent advances in computerization of in-vehicle devices, the number of connectors for use in a vehicle is rapidly increasing. A fitting condition of a connector for connecting wires of an electric system of a vehicle is detected by checking the presence or absence of a sound or checking with eyes during a connector fitting operation, or checking a fitting condition by manual operation, for example, for each connector.
However, the connector fitting operation is carried out in a relatively unfavorable acoustical environment and in a narrow space of a vehicle, so it is difficult to reliably perform the checking for every connector. For this reason, it is difficult to secure a sufficient reliability for checking the fitting. Additionally, a certain time is required for the checking, which hinders an improvement in work efficiency.
In this regard, Patent Document 1 discloses a method for checking a fitting condition of a connector for the purpose of easily checking the fitting condition of the connector also in an assembly line. In this method, a vibration detecting section which is attached to an operator detects a vibration produced by a connector at the time of fitting the connector, converts the vibration detected by the vibration detecting section into vibration waveform data, and transmits it. The vibration waveform data is received, and data unnecessary for determining the fitting condition is removed from the vibration waveform data, thereby generating data for determination. The data for determination thus generated is compared with reference data stored in advance, thereby determining whether the fitting condition of the connector is defective or not.
[Patent Document 1] Japanese Unexamined Patent Application Publication No. 2006-221971